1. Technical Field
The present invention relates to collision avoidance and target identification systems and methods.
2. Discussion of Prior Art
Conventional collision avoidance and target identification systems typically employ the usage of radar technology, as radar continues to present a more facilely implementable and efficiently operable medium of detection. Both short-range radar (SRR) and long-range radar (LRR) enjoy wide application in many industries, such as automotive safety systems, and are often used in over-lapping configuration. In these systems, one or more laterally scanning sensors are oriented and configured to perform a single-dimensional scan of the surrounding environment, so as to detect surficial objects within an operable range. In some configurations, where an object is detected, a trend in the radar return signal strength over a period is assessed to determine whether the target (i.e., detected object) is approaching or departing.
A prevailing concern in conventional radar systems is that they typically generate a significant number of false alerts (i.e. warnings of imminent collisions with objects that are not true threats). This concern is especially perpetuated by their inability to discriminate between objects present at different elevations. For example, in automotive safety applications, false alerts of in-path obstruction are often caused by hyper-elevated objects, such as overhead signs and overpasses, because both SRR and LRR sensors are not capable of determining the elevation of a target. Since signs and overpasses are typically present in great numbers along an interstate highway or other thoroughfare path, the number of false-alerts generated thereby may produce a significant nuisance to the driver. Similarly, many hypo-elevated or low-lying features, such as potholes and railroad tracks, have also generated false alerts.
Where three-dimensional information, such as the height, amplitude or elevation of targets is desired, collision avoidance systems have incorporated stereo vision, two-dimensional scanning Lidar, two-dimensional scanning Radar, or Radar with azimuth and elevation resolution using monopulse, multibeam, phased array or digital beam technology. All of these options, however, present high costs of implementation and operation, and some have performance limitations based on environment.
Thus, there remains a need in the art for a collision avoidance and target identification system that is able to efficiently estimate the elevation of a target, so as to reduce the number of false alerts generated by hyper and hypo-elevated objects.